in which successive cat ##ion trapping generates a pen ##ta ##cy ##cl ##ic core in one step with complete dia ##ster ##eo ##sel ##ect ##ivity . en ##olate trapping with various electro ##phile ##s is decidedly less common . in one study , the na ##zar ##ov cy ##cl ##ization is paired with a michael reaction using an ir ##idium catalyst to initiate nu ##cle ##op ##hil ##ic con ##ju ##gate addition of the en ##olate to β @ - @ ni ##tro ##sty ##ren ##e . in this tandem reaction the ir ##idium catalyst is required for both conversions : it acts as the lewis acid in the na ##zar ##ov cy ##cl ##ization and in the next step the ni ##tro group of ni ##tro ##sty
in which successive cation trapping generates a pentacyclic core in one step with complete diastereoselectivity. enolate trapping with various electrophiles is decidedly less common. in one study, the nazarov cyclization is paired with a michael reaction using an iridium catalyst to initiate nucleophilic conjugate addition of the enolate to β @ - @ nitrostyrene. in this tandem reaction the iridium catalyst is required for both conversions : it acts as the lewis acid in the nazarov cyclization and in the next step the nitro group of nitrosty